The background description provided herein is for the purpose of generally presenting the context of the present invention. The subject matter discussed in the background of the invention section should not be assumed to be prior art merely as a result of its mention in the background of the invention section. Similarly, a problem mentioned in the background of the invention section or associated with the subject matter of the background of the invention section should not be assumed to have been previously recognized in the prior art. The subject matter in the background of the invention section merely represents different approaches, which in and of themselves may also be inventions. Work of the presently named inventors, to the extent it is described in the background of the invention section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present invention.
An impeller washing machine in the prior art usually includes a cabinet, an outer barrel suspended in the cabinet, an inner barrel provided in the outer barrel and actuated by an external rotating shaft to rotate, and an agitator connected to the bottom of the inner barrel through an inner rotating shaft. The bottom of the outer barrel is provided with a drainage valve, and a water inlet of the drainage valve is connected to a drainage port arranged at the bottom of the outer barrel. A filter is usually provided on the wall of the inner barrel, and filters lint passively through water flow during washing. A water pump is provided at the bottom of the outer barrel. A water inlet of the water pump is connected to a drainage pipe at the bottom of the outer barrel. A drainage port of the water pump is connected to a pipe leading to the inner barrel of the washing machine. During washing, when a motor drives the agitator to actuate laundry to rotate, a cyclic water pump runs to recycle washing water at the bottom of the outer barrel and discharge the washing water back to the inner barrel. The filter is provided at a water outlet of a connecting pipe of the water pump to filter lint and impurities in drain water from washing. The washing water that has been filtered may flow back to the inner barrel to clean the washing water. Such filtering apparatus is generally a flexible filtering mesh bag or a rigid filtering frame. After a period of time of use, lint and impurities in the filtering apparatus must be manually removed, otherwise the filtering apparatus would be clogged and bacteria would grow. In addition, when the washing water with lint and impurities enters the water pump, lint and impurities wind on the parts of the water pump. Relatively rigid foreign materials such as paper clips, hair clips or coins may easily cause the failure of the water pump appear. Moreover, damages caused by foreign materials to the water pump cannot be prevented if the filter is arranged on the outlet of the water pump.
Therefore, many manufacturers have made improvements to the foregoing structure. Chinese Patent Application No. 200420120524.6 discloses a cyclic pipe of an inner circulation washing machine, which includes: an outer barrel drainage port arranged at the bottom of an outer barrel, an inner circulation outlet arranged at the top of the outer barrel for sending filtered circulating water into an inner barrel for recycling, an inner circulation pipe for connecting the outer barrel drainage port and the inner circulation outlet, and an inner circulation pump arranged between the outer barrel drainage port and the inner circulation outlet for pressing washing water discharged from the outer barrel drainage port into the inner barrel again, where at least one filtering apparatus is arranged at an input end of the inner circulation pump, which is at the bottom of the outer barrel. The filtering apparatus is for collecting lint and/or paper shreds in circulating water and may be detached for cleaning. However, the structure is relatively complex and has a relatively high requirement of improving the inner circulation pipe. Moreover, the inner circulation pipe is arranged at the bottom of the outer barrel, and the connection between the filtering apparatus and the pipe loosens with the vibration of the outer barrel, which easily causes an undesirable filtering effect of the filtering port, or even causes some foreign materials to directly pass through the filtering apparatus and cannot be completely filtered, resulting in damages to the water pump.
Chinese Patent Application No. 200610036929.5 discloses a washing machine with a cyclic water pump. The washing machine includes an outer barrel suspend in a cabinet and an inner barrel located in the outer barrel and actuated by an external rotating shaft to rotate, and a drainage passage for discharging water in the outer barrel out of the cabinet. The upstream of a water inlet of the water pump is connected with the bottom of the outer barrel, and the downstream of a drainage port at the bottom of the outer barrel is connected with a pipe leading to the inner barrel of the washing machine. A filtering apparatus is provided at the upstream of the water inlet of the water pump, and a filtering surface of the filtering apparatus is arranged at the drainage passage and close to the upstream of the water inlet of a drainage valve. After long term use, the structure may easily cause lint to clog the filtering apparatus.
Moreover, an impeller washing machine with a drainage pump discharges water in the washing machine under the effect of the drainage pump. However, no effective filtering apparatus is provided. And after long term use of the washing machine, a large quantity of foreign materials enters a drainage valve or the drainage pump and cannot be removed. In severe cases, foreign materials may result in a drainage apparatus not discharging waste water, causing inconvenience or even economical loss to a user.
Therefore, a heretofore unaddressed need exists in the art to address the aforementioned deficiencies and inadequacies.